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Hydrophobic ion pairing (HIP) complexation was found to be an efficient approach in modulating the release and enhancing the stability and encapsulation of hydrophilic macromolecules such as proteins in hydrophobic nano/microcarriers. The present work strives to develop and optimize the preparation of the HIP complex of the antimicrobial enzyme lysozyme (LYZ) with the ion-pairing agent (IPA) sodium dodecyl sulphate (SDS) relying on the quality-by-design (QbD) approach. The quality target product profile (QTPP) includes the achievement of maximal lipophilicity in a reversible manner to enable the maintenance of biological activity. The related critical quality attributes (CQAs) were defined as complexation efficacy, complex stability, enzyme recovery and activity. Three risk assessment (RA) tools were used to identify and rank the critical process parameters (CPPs) and critical material attributes (CMAs). From this assessment, the pH of the medium, LYZ:SDS molar ratio and drying conditions were determined as high-risk factors that need to be investigated. To the best of our knowledge, for the first time, electrostatic titration was used as a smart approach to determine the optimum molar ratio at different pH values. Based on the predefined CQAs, pH 8 with an LYZ/SDS molar ratio of 1:8 was found to be the optimal condition for complexation efficiency and recovery (%) of a biologically active enzyme. A cost-effective drying process based on a ventilated oven was developed, which resulted in complex qualities comparable to those obtained by the commonly used freeze-drying method. In a nutshell, the optimum conditions for the preparation of the LYZ/SDS HIP complex were efficiently facilitated by the rational application of QbD principles and the utilization of efficient electrostatic titration and ventilated oven-drying methods. [ABSTRACT FROM AUTHOR]

Polysaccharides are another important class of bioactive macromolecules in organisms, in addition to proteins and nucleic acids. Numerous studies have confirmed that polysaccharides have various biological activities, including anti‐inflammatory, antiviral, antioxidant, immunomodulatory, anticancer, and other activities, which have attracted the attention of researchers in the biomedical field. In the past decade, increasing researches have found that sulfation modification can improve many physicochemical properties of polysaccharides, significantly enhance their original biological activities, and even generate new activity. Hence, sulfated polysaccharides have attracted more and more attention. A systematic review of the latest research progress and future development prospects of sulfated polysaccharides is very essential to better understand them. Hence, the study has systematically summarized current knowledge about synthesis, structural characteristics, biological activities, and potential molecular mechanisms of sulfated polysaccharides. This review provides some valuable insights and important guidance for the further study of sulfated polysaccharides. [ABSTRACT FROM AUTHOR]

A novel method for extraction, separation, and trace determination of thorium(IV) with calix[4]resorcinarene-2, 8, 14, 20-tetrakis[N-phenylbenzo]-hydroxamic acid (C4RATHA) is described. The thorium (IV) is extracted from an n-octanol solution of C4RATHA at a pH of 4.5, as colorless extract with a maximum absorption at 375 nm and molar absorptivity of 1.5 × 104 L mol−1 cm−1. The extract is then analyzed using ICP-AES, and a linear calibration graph is obtained between 35.88 and 309.40 ng mL−1 with a detection limit of 20 ng mL−1. The method is applied be used to measure thorium (IV) in monazite sand and rare earth sand in the presence of other diverse ions. The thorium is recovered from seawater and analyzed. [ABSTRACT FROM AUTHOR]

This work aimed at studying the self‐assembly of lignin macromolecules towards lignin nanoparticles (LNPs) with green solvents and shedding light on a tailor‐made production of LNPs through a meticulous study of different variables. The methodology (antisolvent to lignin solution – method A; or lignin solution to antisolvent – method B), the lignin solvent, the flow rate of solvent/antisolvent addition, the lignin solution loading and the washing step (centrifugation vs dialysis) were examined. Remarkably, method B enabled achieving desired LNPs (127.4–264.9 nm), while method A induced the formation of lignin microparticles (582.8–7820 nm). Among lignin solvents, ethanol allowed the preparation of LNPs with the lowest hydrodynamic diameter (method B=127.4 nm), while the largest particles (method A=7820 nm) were obtained with ethylene glycol. These latest particles were characterized as heterogeneous, irregular, and highly aggregated when compared for instance with γ‐valerolactone counterparts, which showed the most homogeneous (PDI=0.057–0.077) and spherical particles. Moreover, decreasing lignin solution loading enabled the reduction on LNP size and Zeta potential. Dialysed samples allowed the formation of LNPs with lower hydrodynamic size, reduced aggregation, and higher homogeneity. Furthermore, dialysis provided high stability to LNPs, avoiding particle coalescent phenomenon. [ABSTRACT FROM AUTHOR]

This study analyses the formation of complexes between soy protein isolate (SPI) and phenolic compounds in hydro- ethanolic extract of pomegranate peel (ePGP) and the effects of protein- phenolic interaction on the structure and physicochemical properties of the protein. The complexes (SPI-ePGPs) were obtained under conditions of different pH: acidic (3.0, 4.0, 5.0), neutral (7.0) and alkaline (7.5 and 9.0), and with pre- treatment of SPI at a temperature of 90ºС and 25ºС. The formation of SPI-ePGPs was established by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE) and UV- Vis spectroscopy. The results show that phenolic compounds change the structure of SPI, and they are most distinct in the alkali-treated SPI-ePGPs. The effect of the interaction between SPI macromolecules and phenolic compounds on protein solubility as well as foam formation and stability in SPI- ePGPs was monitored. In the complexes created, the phenolic compounds in ePGP did not increase the solubility of the protein, but had a positive effect on foaming. The research data provide a theoretical basis for creating methods for modifying soy protein and for developing new food and matrix systems for active substances in the pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing is vital in recovering hydrocarbons from oil and gas reservoirs. It involves injecting a fluid under high pressure into reservoir rock. A significant part of fracturing fluids is the addition of polymers that become gels or gel-like under reservoir conditions. Polymers are employed as viscosifiers and friction reducers to provide proppants in fracturing fluids as a transport medium. There are numerous systems for fracturing fluids based on macromolecules. The employment of natural and man-made linear polymers, and also, to a lesser extent, synthetic hyperbranched polymers, as additives in fracturing fluids in the past one to two decades has shown great promise in enhancing the stability of fracturing fluids under various challenging reservoir conditions. Modern innovations demonstrate the importance of developing chemical structures and properties to improve performance. Key challenges include maintaining viscosity under reservoir conditions and achieving suitable shear-thinning behavior. The physical architecture of macromolecules and novel crosslinking processes are essential in addressing these issues. The effect of macromolecule interactions on reservoir conditions is very critical in regard to efficient fluid qualities and successful fracturing operations. In future, there is the potential for ongoing studies to produce specialized macromolecular solutions for increased efficiency and sustainability in oil and gas applications. [ABSTRACT FROM AUTHOR]

The phase structure of polypropylene thermoplastic elastomer (PTPE) is always a multiphase system in the preparation process. Under the condition of limited compatibility between polypropylene (PP) and elastomer, it is difficult to control the dispersion uniformity, size and morphology of each component domain between PP and elastomer. In order to make PTPE have homogeneous domains, easily controlled morphology and structure, and stable mechanical properties, microphase separation PP thermoplastic elastomer (MS-PTPE) was prepared based on the homogeneous system of PP and elastomer, and the chemical structure of MS-PTPE was studied by fractional extraction method. The results show that MS-PTPE is composed of unreacted PP, unreacted elastomer, graft copolymer of PP and (or) elastomer with bridging agent chain, and crosslink between elastomer and PP macromolecules with polymeric bridging chain formed by bridging agent. The chemical structure of MS-PTPE was significantly affected by different proportion of elastomer, different dosage of initiator and different dosage of bridging agent, and there was a certain synergistic effect between the dosage of initiator and bridging agent. [ABSTRACT FROM AUTHOR]

The simplified molecular-input line-entry system (SMILES) has been utilized in a variety of artificial intelligence analyses owing to its capability of representing chemical structures using line notation. However, its ease of representation is limited, which has led to the proposal of BigSMILES as an alternative method suitable for the representation of macromolecules. Nevertheless, research on BigSMILES remains limited due to its preprocessing requirements. Thus, this study proposes a conversion workflow of BigSMILES, focusing on its automated generation from SMILES representations of homopolymers. BigSMILES representations for 4,927,181 records are provided, thereby enabling its immediate use for various research and development applications. Our study presents detailed descriptions on a validation process to ensure the accuracy, interchangeability, and robustness of the conversion. Additionally, a systematic overview of utilized codes and functions that emphasizes their relevance in the context of BigSMILES generation are produced. This advancement is anticipated to significantly aid researchers and facilitate further studies in BigSMILES representation, including potential applications in deep learning and further extension to complex structures such as copolymers. [ABSTRACT FROM AUTHOR]

The interaction of pectin and arabinogalactan macromolecules in aqueous solutions has been studied. It is shown that polymer complexes are formed due to hydrogen bonding between macromolecules. Crosslinking of the polymer complex by Са2+ ions leads to the formation of hydrogels whose properties are considerably determined by the content of arabinogalactan. At low concentrations of Са2+ ions (from 0.05 to 0.15 wt %), the introduction of arabinogalactan contributes to an increase in shear modulus and crosslink concentration and results in a reduction in polymer network sizes compared with hydrogels based on native pectin. With increasing arabinogalactan content the contribution of Fick's diffusion to swelling of the synthesized hydrogels grows. [ABSTRACT FROM AUTHOR]

Rheological analysis of citrus pectin at pH 3 and 7 elucidates its structural dynamics, revealing distinct behaviors influenced by pH. At pH 3, pectin exhibits shear-thinning, with solvent-independent unified rheological profiles identifying three concentration regimes: 0.5%-1.5%, 2%-3%, and 3.5%-4%. These regimes, alongside Cox--Merz superpositions, outline the semi-dilute (c*) and concentrated (c**) transitions at 1.5%-2% and 3%-3.5%, respectively. Moreover, a Morris equation exponent of 0.65 indicates flexible, mobility-restricted macromolecules. Conversely, at pH 7, increased viscosities and Morris plot linearity for p = .1 suggest rigid chain behavior due to electrostatic repulsion among ionized acidic groups. This rigidity leads to concentration-dependent self-assembly structures that diverge from expected unified rheological profiles, a deviation amplified by heating--cooling cycles. This study clarifies the impact of pH on citrus pectin's rheology and emphasizes the intricate relationship between polymeric chain rigidity, self-assembly, and viscosity. By providing a refined understanding of these mechanisms, our findings contribute to the broader field of polysaccharide research, offering insights critical for developing and optimizing pectin-based applications in various industries. [ABSTRACT FROM AUTHOR]

A new method of determining the dimensions and shapes of polymer molecules in solutions is proposed and verified in experiments. The method is based on the measurements of the relaxation of the transverse magnetization intensity of nuclei. It is established that the decaying signal of the spin echo from elongated molecules contains two terms exponentially decaying with time, which correspond to two diffusion coefficients differing by a factor of about two. The signal from molecules with a near-spherical shape contain only one exponent. [ABSTRACT FROM AUTHOR]

The microstructure of polymer chain of low molecular weight polybutadienes synthesized with cationic initiating systems has been investigated using one-dimensional (13C, 13C with a T2-filter, and 13C DEPT-135°) and two-dimensional 1H—13C (HSQC and HMBC) NMR spectroscopy. It was found that the unsaturated part of main polymer chain consists of 1,4-trans- and 1,2-structures with different combination of units. For the first time, structures of the head groups of polymers were identified, which are dimethylpropane fragments of the initiator (2-chloro-2-methyl-butane) connected with 1,4-trans- or 1,2-units of polybutadiene. Structures of two types (1,4-trans- and 1,2-) of chlorine-containing end groups were found. Methods for the calculation of the content of head and end groups, unsaturation and functionality of polybutadiene macromolecules on the terminal groups were developed. [ABSTRACT FROM AUTHOR]

The growing interest in functional materials has resulted in the emergence of smart polymers, demonstrating practical performance in various applications especially for biomedical purposes. The properties of functional polymers are mainly determined by the presence of functional groups that differ from those in the main chains. While some polymers are naturally active and considered functional, others require modification for enhanced impact and functionality. Many functional polymers typically have a linear backbone, but very recently the attention has been shifted towards those with specific topologies and architecture, for example, bottlebrushes, stars, dendritic polymers, and gels. Over the past few years, there has been a rising emphasis on integrating selective bonds into complex polymer structures to enhance chain scission in single macromolecules. This review captures the most recent and promising approaches to the design of non-linear functional polymers containing selective/cleavable bonds and discusses the potential of these materials for biomedical applications. [ABSTRACT FROM AUTHOR]

Dry mouth, also known as xerostomia, is a condition in which insufficient or ineffective saliva does not provide sufficient oral lubrication. The severity of this condition can vary from a mild discomfort to a debilitating condition that greatly impairs patients' lives. Xerostomia arises as a side effect of various medications, diseases, radiation therapy, chemotherapy, or nerve damage. Various aqueous dispersions of macromolecules have been proposed to assist or replace the saliva in these patients. It is vital that these macromolecules have ample lubricity and water retention properties while showing long-lasting efficacy. The emphasis of this review is to provide a general overview on lubricating macromolecules that have been clinically used or reported in the literature as potential replacements for saliva. These include various natural or synthetic polymers, proteins, peptides, and lipids that are used in the form of solutions, gels, emulsions, and colloids. Perspectives into the future of macromolecular oral lubricants in the treatment of xerostomia are also provided. [ABSTRACT FROM AUTHOR]

Purpose: Absolute spectral quantification is the standard method for deriving estimates of the concentration from metabolite signals measured using in vivo proton MRS (1H‐MRS). This method is often reported with minimum variance estimators, specifically the Cramér‐Rao lower bound (CRLB) of the metabolite signal amplitude's scaling factor from linear combination modeling. This value serves as a proxy for SD and is commonly reported in MRS experiments. Characterizing the uncertainty of absolute quantification, however, depends on more than simply the CRLB. The uncertainties of metabolite‐specific (T1m, T2m), reference‐specific (T1ref, T2ref), and sequence‐specific (TR, TE) parameters are generally ignored, potentially leading to an overestimation of precision. In this study, the propagation of uncertainty is used to derive a comprehensive estimate of the overall precision of concentrations from an internal reference. Methods: The propagated uncertainty is calculated using analytical derivations and Monte Carlo simulations and subsequently analyzed across a set of commonly measured metabolites and macromolecules. The effect of measurement error from experimentally obtained quantification parameters is estimated using published uncertainties and CRLBs from in vivo 1H‐MRS literature. Results: The additive effect of propagated measurement uncertainty from applied quantification correction factors can result in up to a fourfold increase in the concentration estimate's coefficient of variation compared to the CRLB alone. A case study analysis reveals similar multifold increases across both metabolites and macromolecules. Conclusion: The precision of absolute metabolite concentrations derived from 1H‐MRS experiments is systematically overestimated if the uncertainties of commonly applied corrections are neglected as sources of error. [ABSTRACT FROM AUTHOR]

Since methods for reducing macromolecule entanglements have been developed, it has become possible to better understand the impact of polymer chain entanglement on the crystallization process. The article presents basic information about the disentangling of macromolecules and the characterization of the degree of entanglement. The basic knowledge of polymer crystallization was also presented. Then, it was discussed how polymers crystallize during their disentangling. Non-isothermal and isothermal crystallization experiments using disentangled polymers, and for comparison using entangled polymers, are described in more detail. The influence of disentangling on both nucleation and crystal growth is highlighted. It is also shown how the crystallization of polymers changes when macromolecules re-entangle. [ABSTRACT FROM AUTHOR]

Relevance. The use of anti-turbulent additives for transporting hydrocarbon liquids through main pipelines allows reducing significantly the energy consumption of pumping power stations. Aim. Comparative analysis of the anti-turbulent efficiency of high-molecular polymers and compositions of surfactants. Methods. Laboratory-scale experimentation aimed to study the flow of dilute polymer solutions and dispersed surfactant systems through a cylindrical channel of a turbulent rheometer. Results. The author has carried out the comparative experimental studies of the anti-turbulent efficiency of extremely dilute solutions of polymers and colloidal systems. The results were obtained that suggest a higher anti-turbulent efficiency of high-molecular-weight polymers compared to micellar surfactant systems. Solutions of high molecular weight polybutadiene and aluminum polyhydroxydicarboxylates in gasoline were used as samples for the experimental comparison of hydrodynamic efficiency. The paper describes the laboratory setup, on which the studies were carried out, and introduces the formulas used for quantitative calculations. The structure of polymer solutions and colloidal systems is considered and a theoretical explanation is given for the preferential use in industrial practice of high-molecular polymers in extremely low concentrations in real pipelines. It was found out that the mechanisms of degradation of antiturbulent properties of polymer solutions and dispersed surfactant systems are different. This is due to the difference in the structure of macromolar coils of polymer with an immobilized solvent and that of micelles from low molecular amphiphilic compounds. The paper introduces the arguments that explain the degradation of the antiturbulent properties of polymers not by the destruction of carbon-chain macromolecules, but by decomposition in a turbulent flow of the original large associates, consisting of a large number of chains, into individual and smaller macromolecular coils with an immobilized solvent.

Abstract Peritoneal membrane dysfunction in peritoneal dialysis (PD) is primarily attributed to angiogenesis; however, the integrity of vascular endothelial cells can affect peritoneal permeability. Hyaluronan, a component of the endothelial glycocalyx, is reportedly involved in preventing proteinuria in the normal glomerulus. One hypothesis suggests that development of encapsulating peritoneal sclerosis (EPS) is triggered by protein leakage due to vascular endothelial injury. We therefore investigated the effect of hyaluronan in the glycocalyx on peritoneal permeability and disease conditions. After hyaluronidase-mediated degradation of hyaluronan on the endothelial cells of mice, macromolecules, including albumin and β2 microglobulin, leaked into the dialysate. However, peritoneal transport of small solute molecules was not affected. Pathologically, hyaluronan expression was diminished; however, expression of vascular endothelial cadherin and heparan sulfate, a core protein of the glycocalyx, was preserved. Hyaluronan expression on endothelial cells was studied using 254 human peritoneal membrane samples. Hyaluronan expression decreased in patients undergoing long-term PD treatment and EPS patients treated with conventional solutions. Furthermore, the extent of hyaluronan loss correlated with the severity of vasculopathy. Hyaluronan on endothelial cells is involved in the peritoneal transport of macromolecules. Treatment strategies that preserve hyaluronan in the glycocalyx could prevent the leakage of macromolecules and subsequent related complications.

Chitin, the second most abundant biopolymer after cellulose, is an important resource for biosourced materials. The global demand for chitin is rapidly increasing, however, the majority of industrial chitin is sourced from crustacean shells, which may be less accessible in regions without seafood waste. Therefore, it is crucial to explore alternative chitin sources, such as those derived from beetles and other arthropods. This study investigated chitin extraction from nine species of Curculionidae (true weevils), which are recognized as crop pests. The extraction process and yields were described, and the isolated chitin was characterized by SEM, IR spectroscopy, elemental analysis, XRD, and ash and water content measurements. This work highlights the potential of Curculionidae as an alternative chitin source.

Progress in sorting, separating, and characterizing ever smaller amounts of chemical and biological material depends on the availability of methods for the controlled interaction with nanoscale and molecular-size objects. Here, we report on the reversible, tunable trapping of single DNA molecules and other charged micro- and nanoparticles in aqueous solution using a direct-current (DC) corral trap setup. The trap consists of a circular, non-conductive void in a metal-coated surface that, when charged, generates an electrostatic potential well in the proximate solution. Our results demonstrate that stable, nanoscale confinement of charged objects is achievable over extended periods of time, that trap stiffness is controlled by the applied voltage, and that simultaneous trapping of multiple objects is feasible. The approach shows great promise for lab-on-a-chip systems and biomedical applications due to its simplicity, scalability, selectivity, and the capability to manipulate single DNA molecules in standard buffer solutions. [ABSTRACT FROM AUTHOR]

Bottlebrush polymers are a class of highly branched macromolecules that show promise for applications such as self-assembled photonic materials and tunable elastomers. However, computational studies of bottlebrush polymer solutions and melts remain challenging due to the high computational cost involved in explicitly accounting for the presence of side chains. Here, we consider a coarse-grained molecular model of bottlebrush polymers where the side chains are modeled implicitly, with the aim of expediting simulations by accessing longer length and time scales. The key ingredients of this model are the size of a coarse-grained segment and a suitably coarse-grained interaction potential between the non-bonded segments. Prior studies have not focused on developing explicit forms of such potentials, instead, relying on scaling arguments to model non-bonded interactions. Here, we show how to systematically calculate an interaction potential between the coarse-grained segments of bottlebrush from finer grained explicit side chain models using Monte Carlo and Brownian dynamics and then incorporate it into an implicit side chain model. We compare the predictions from our coarse-grained implicit side chain model with those obtained from models with explicit side chains in terms of the potential of mean force, the osmotic second virial coefficient, and the interpenetration function, highlighting the range of applicability and limitations of the coarse-grained representation. Although presented in the context of homopolymer bottlebrushes in athermal solvents, our proposed method can be extended to other solvent conditions as well as to different monomer chemistries. We expect that our implicit side chain model will prove useful for accelerating large-scale simulations of bottlebrush solutions and assembly. [ABSTRACT FROM AUTHOR]

Compartmentalization protected biomolecules from the fluctuating environments of early Earth. Although contemporary cells mostly use phospholipid‐based bilayer membranes, the utility of non‐bilayer compartments was not ruled out during the prebiotic and modern eras. In the present study, we demonstrated the prebiotic synthesis of lipidated cationic amino acid‐based amphiphiles [lauryl ester of lysine (LysL); ornithine (OrnL); and 2,4‐diamino butyric acid (DabL)] using model dry‐down reaction. These amphiphiles self‐assemble into micellar membranes. However, the OrnL and DabL‐based micelles undergo pH‐responsive transformation to lipid droplet‐like morphologies, a modelcompartment in the prebiotic Earth. These cationic droplets encapsulated prebiotic molecules (isoprene) and assisted electron transfer reaction to synthesize isoprenoid derivatives at primitive Earth conditions. The self‐assembly of prebiotic amphiphiles, their transformation to droplet compartments, and droplet‐assisted C−C bond formation reaction might have helped the evolution to synthesize various biomolecules required for the origin of life. [ABSTRACT FROM AUTHOR]

Diffusiophoresis is the isothermal migration of a colloidal particle through a liquid caused by a cosolute concentration gradient. Although diffusiophoresis was originally introduced using hydrodynamics, it can also be described by employing the framework of multicomponent diffusion. This not only enables the extraction of diffusiophoresis coefficients from measured multicomponent-diffusion coefficients but also their theoretical interpretation using fundamental thermodynamic and transport parameters. This review discusses the connection of diffusiophoresis with the 2 × 2 diffusion-coefficient matrix of ternary liquid mixtures. Specifically, diffusiophoresis is linked to the cross-term diffusion coefficient characterizing diffusion of colloidal particles due to cosolute concentration gradient. The other cross-term, which describes cosolute diffusion due to the concentration gradient of colloidal particles, is denoted as osmotic diffusion. Representative experimental results on diffusiophoresis and osmotic diffusion for polyethylene glycol and lysozyme in the presence of aqueous salts and osmolytes are described. These data were extracted from ternary diffusion coefficients measured using precision Rayleigh interferometry at 25 °C. The preferential-hydration and electrophoretic mechanisms responsible for diffusiophoresis are examined. The connection of diffusiophoresis and osmotic diffusion to preferential-interaction coefficients, Onsager reciprocal relations, Donnan equilibrium and Nernst–Planck equations are also discussed. [ABSTRACT FROM AUTHOR]

Single-particle cryo-electron microscopy (cryo-EM) has been shown to be effective in defining the structure of macromolecules, including protein complexes. Complexes adopt different conformations and compositions to perform their biological functions. In cryo-EM, the protein complexes are observed in solution, enabling the recording of images of the protein in multiple conformations. Various methods exist for capturing the conformational variability through analysis of cryo-EM data. Here, we analyzed the conformational variability in the hexameric AAA + ATPase p97, a complex with a six-fold rotational symmetric core surrounded by six flexible N-domains. We compared the performance of discrete classification methods with our recently developed method, MDSPACE, which uses 3D-to-2D flexible fitting of an atomic structure to images based on molecular dynamics (MD) simulations. Our analysis detected a novel conformation adopted by approximately 2% of the particles in the dataset and determined that the N-domains of p97 sway by up to 60° around a central position. This study demonstrates the application of MDSPACE in analyzing the continuous conformational changes in partially symmetrical protein complexes, systems notoriously difficult to analyze due to the alignment errors caused by their partial symmetry. [ABSTRACT FROM AUTHOR]

Stressed soft materials commonly present viscoelastic signatures in the form of power-law or exponential decay. Although exponential responses are the most common, power-law time dependencies arise peculiarly in complex soft materials such as living cells. Understanding the microscale mechanisms that drive rheologic behaviors at the macroscale shall be transformative in fields such as material design and bioengineering. Using an elastic network model of macromolecules immersed in a viscous fluid, we numerically reproduce those characteristic viscoelastic relaxations and show how the microscopic interactions determine the rheologic response. The macromolecules, represented by particles in the network, interact with neighbors through a spring constant k and with fluid through a non-linear drag regime. The dissipative force is given by γvα, where v is the particle's velocity, and γ and α are mesoscopic parameters. Physically, the sublinear regime of the drag forces is related to micro-deformations of the macromolecules, while α ≥ 1 represents rigid cases. We obtain exponential or power-law relaxations or a transitional behavior between them by changing k, γ, and α. We find that exponential decays are indeed the most common behavior. However, power laws may arise when forces between the macromolecules and the fluid are sublinear. Our findings show that in materials not too soft not too elastic, the rheological responses are entirely controlled by α in the sublinear regime. More specifically, power-law responses arise for 0.3 ⪅ α ⪅ 0.45, while exponential responses for small and large values of α, namely, 0.0 ⪅ α ⪅ 0.2 and 0.55 ⪅ α ⪅ 1.0. [ABSTRACT FROM AUTHOR]

Glycosaminoglycans (GAGs) are important for the occurrence of signaling molecules and maintenance of microenvironment within the extracellular matrix (ECM) in living tissues. GAGs and GAG‐based biomaterial approaches have been widely explored to promote in situ tissue regeneration and repair by regulating the wound microenvironment, accelerating re‐epithelialization, and controlling ECM remodeling. However, most approaches remain unacceptable for clinical applications. To improve insights into material design and clinical translational applications, this review highlights the innate roles and bioactive mechanisms of native GAGs during in situ wound healing and presents common GAG‐based biomaterials and the adaptability of application scenarios in facilitating wound healing. Furthermore, challenges before the widespread commercialization of GAG‐based biomaterials are shared, to ensure that future designed and constructed GAG‐based artificial biomaterials are more likely to recapitulate the unique and tissue‐specific profile of native GAG expression in human tissues. This review provides a more explicit and clear selection guide for researchers designing biomimetic materials, which will resemble or exceed their natural counterparts in certain functions, thereby suiting for specific environments or therapeutic goals. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) encompass a diverse array of cell-derived vesicles, originating either from the endosomal compartment (exosomes) or generated through shedding from the cell membrane. These lipid bilayer nanovesicles carry a diverse cargo consisting of nucleic acids, various macromolecules, and growth factors, capable of being assimilated by nearby or distant cells through biofluids, thereby triggering a wide range of cellular responses. Given their distinctive biological characteristics and crucial roles in intercellular communication, EVs have garnered significant attention, especially concerning potential clinical applications. Inheriting cargo from their parent cells, EVs present promising resources for diverse disease biomarkers. Research elucidating the specific impacts of cargo on target cells has sparked enthusiasm for their therapeutic potential. Compelling evidence indicates that RNA cargo housed within EVs can modulate gene expression and influence cellular functions in recipient cells. However, despite significant progress, numerous aspects of EV biology remain obscure, encompassing selective cargo-loading mechanisms that yield distinct compositions from source cells, variability in size and content, and undisclosed pathways governing uptake and cargo fate in recipient cells. A thorough understanding of core EV mechanisms—such as generation, trafficking, and payload delivery—is essential for their effective clinical utilization. This review explores the current understanding of RNA loading and transportation within EVs, shedding light on the advancements made toward clinical applications. [ABSTRACT FROM AUTHOR]

Foods comprise of many macromolecules that have varying techno-functional and nutritional properties. The isolated proteins and carbohydrates from them are increasingly being used as potential ingredients in the food industries. Numerous processes like drying for food processing and preservation cause variations in functional and nutritional attributes of proteins and carbohydrates in different degrees in the food products that can ultimately affect their possible applications. This article explores different drying technologies being used in the food industries, including freeze-drying, microwave-assisted drying, infrared drying, vacuum drying, spray drying, and oven drying. Based on the evaluation of multiple studies, it can be inferred that these drying methods have the potential to contribute to low drying performance, high operational costs, and strong environmental impact. Moreover, they can affect the nutritional value of macronutrients such as proteins, starches, gums, and dietary fibers present in foods, the integrity of the food structures, and their functional properties. Understanding the correlation between the drying technique used and the functional and nutritional attributes of macromolecules will help to provide better insight into the importance of the different drying methods. Optimization of the operational parameters of the different drying methods could be vital and needs to be evaluated to avoid the degradation of the proteins and carbohydrates and the loss of their properties. [ABSTRACT FROM AUTHOR]

The study of large biomolecules, in particular DNA, is of practical interest. Marker bands of the Raman spectrum of DNA provide information about the conformational state and structure of the macromolecule. At the same time, when dealing with biological experiments, a small amount of DNA is available, which is why it is important to enhance the signal from DNA and find the proper substrate. However, it is difficult to enhance Raman spectra for large molecules as DNA without functionalization that could introduce changes in the DNA structure. In this work, a conventional substrate as CaF2 and a photonic crystal as a substrate with enhancer signal property and without DNA functionalization were applied. The factor of enhancement for DNA from salmon testes was reached up to 10 without Raman spectra distortion. The Raman spectral bands on different types of substrates are analyzed and compared. [ABSTRACT FROM AUTHOR]

Recent studies have shown the importance of using highly resolved models for Brownian Dynamics (BD) simulations of long macromolecules. For computational efficiency, such models use stiff springs to mimic a single Kuhn step and use a single-step semi-implicit (SS) scheme. Somewhat unexpectedly, time step sizes for such a single-step method need to be reduced with increasing chain size and level of hydrodynamic interactions (HIs), for good convergence. The conventional predictor–corrector (PC) method works reasonably well but remains computationally slow, owing to multiple iterations per time step to convergence. In this study, we reveal how the time step size for the much faster SS method is tied to the physics of the problem. Using simple physical principles, we derive an analytical estimate of the upper limit on the time step size for given levels of HI, chain size, and stiffness of connecting springs. Detailed BD simulations at equilibrium and in flow fields highlight the success of our analytical estimate. We also provide a lower limit on spring stiffness parameter such that it remains effectively rigid and successfully mimics a Kuhn step. Our investigations show that the resulting BD simulations using our estimated time step size in the SS scheme are significantly faster than the conventional PC technique. The analysis presented here is expected to be useful in general for any type of simulations of macromolecules, with or without flow fields, owing to deep connections with the underlying physics. [ABSTRACT FROM AUTHOR]

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The ionic liquid, as a new treatment agent, has been increasingly applied in oil fields due to its strong temperature resistance, good solubility and high surface activity. In this paper, we systematically discuss the action mechanism and application effect of ionic liquids in oilfield chemistry. Ionic liquids can inhibit shale hydration expansion and reduce fluid loss through adsorption and intercalation, inhibit the formation of natural gas hydrate through imidazole five-membered ring structure as a space barrier, reduce viscosity of heavy oil by breaking chemical bonds of heavy oil macromolecules and charge transfer, improve oil displacement efficiency by forming ions pairs with carboxyl groups in crude oil, demulsify by forming channels between dispersed water droplets, acidify the formation by reacting with water to produce acid, interacts with organic material through weak hydrogen bonds and extracts it from oilfield wastewater, desulphurize by inserting sulfide molecules into the "stack" structure and form liquid inclusion complex, inhibit corrosion by forming a protective film on the metal surface. Based on the above aspects, the development direction of ionic liquids is proposed. The application of ionic liquids in oilfield chemistry is still in its infancy. It is urgent to fully explore the application performance of ionic liquids in oilfield chemistry, which also provides theoretical and technical supports for efficient reservoir development. [ABSTRACT FROM AUTHOR]

Coordination-driven self-assembly processes often produce remarkable structures. In particular, self-assembly processes mediated by chiral template units have provided research ideas for analyzing the formation of chiral macromolecules in living organisms. In this study, by regulating the proportion of reaction raw materials in the "one-pot" synthesis of lanthanide complexes, we constructed chiral template units with different coordination orientations. As a result, lanthanide chiral chains connected to different structures were obtained through the self-assembly process of coordination recognition. In particular, driven by coordination, chiral template units with codirectional coordination points (called cis configuration) coordinate solely with cis template units during the self-assembly process to obtain a one-dimensional (1D) chain R-1 / S-1 with an "S"-shaped distribution. Moreover, chiral template units with reversed coordination sites (called trans configuration) and twisted chiral template units are connected solely to templates with the same configuration to form a 1D chain R-2 / S-2 with an axial helix. A circular dichroism spectrum shows that R-1 / S-1 and R-2 / S-2 are two pairs of enantiomers. The controllable construction of these two differential 1D chains is of great significance for studying coordination recognition at the molecular level. To the best of our knowledge, this is the first study to construct a 1D lanthanide chain through the self-assembly process of coordination recognition. The assembly process of nucleotides to form a hierarchical structure is simulated. This work provides a vivid example of the controllable synthesis of lanthanide complexes with precise structures and offers a new perspective on the formation process of chiral macromolecules that simulates natural processes. [ABSTRACT FROM AUTHOR]

Natural fiber composites are gaining popularity in manufacturing due to their cost-effectiveness, sustainability, reusability, and eco-friendly nature. Kenaf fiber is increasingly used as a reinforcing component in organic fiber-strengthened polymers for engineering purposes. Drilling is a crucial machining process used to create holes in composite constructions for the easier assembly of complex parts. Limited research has focused on drilling organic fiber-strengthened materials, as indicated by literature surveys. Consequently, this study investigates the drilling of weaved kenaf fiber-augmented polymeric composites. The study assesses the impact of drill bit varieties and cutting settings on delamination size and thrust force in poly (lactic acid) (PLA) composites supplemented with kenaf fibers. The investigation revealed that drill bit selection significantly influences surface finish and delamination index. Feed is the cutting variable that, when drilling kenaf fiber-reinforced materials, has the most impact on the thrust force for every drill bit. When using an HSS twisting drill with the Coro Drill-856 (CD-856), the thrust force produced is less than when using the Coro Drill (CD-854) design. [ABSTRACT FROM AUTHOR]

Extracellular enzymes play important roles in myxobacteria degrading macromolecules and preying on other microorganisms. Glycoside hydrolases 19 (GH19) are widely present in myxobacteria, but their evolution and biological functions have not been fully elucidated. Here we investigated the comparative secretory proteome of Corallococcus silvisoli c25j21 in the presence of cellulose and chitin. A total of 313 proteins were detected, including 16 carbohydrate-active enzymes (CAZymes), 7 of which were induced by cellulose or chitin, such as GH6, GH13, GH19, AA4, and CBM56. We further analyzed the sequence and structural characteristics of its three GH19 enzymes to understand their potential functions. The results revealed that myxobacterial GH19 enzymes are evolutionarily divided into two clades with different appended modules, and their different amino acid compositions in the substrate binding pockets lead to the differences in molecular surface electrostatic potentials, which may, in turn, affect their substrate selectivity and biological functions. Our study is helpful for further understanding the biological functions and catalytic mechanisms of myxobacterial CAZymes. [ABSTRACT FROM AUTHOR]

In the last decade, isocyanide‐based multicomponent reactions, like the Passerini three‐component reaction (P‐3CR), have gained significant interest in the synthesis of sequence‐defined macromolecules due to their high efficiency and straightforward one‐pot procedures. The P‐3CR results in unique product structures that are particularly interesting for the synthesis of uniform, branched macromolecules, as they enable the direct introduction of a new branching point into the molecule. In this work, the synthesis of uniform first‐generation dendrons is performed via the P‐3CR using a divergent approach, utilizing three uniform and poorly soluble oligo(phenylene ethynylene)s (OPEs) of varying lengths as a focal moiety. Self‐assembly of the dendrons in cyclohexane solution is confirmed by fluorescence spectroscopy and diffusion‐ordered NMR (DOSY NMR) spectroscopy, highlighting the utility of DOSY NMR spectroscopy for the investigation of solution self‐assembly. Diffusion coefficients for the dendrons and their aggregates are determined and compared for different lengths of the OPE focal moiety. The successful synthesis of the dendrons in good yields and the selective branching introduced on the OPEs by the P‐3CR emphasize the high efficiency and synthetic advantages of multicomponent reactions for the preparation of uniform, branched macromolecules. [ABSTRACT FROM AUTHOR]

Cells are small, closed spaces filled with various types of macromolecules. Although it is shown that the characteristics of biochemical reactions in vitro are quite different from those in living cells, the role of the co‐existence of various macromolecules in cell‐size space remains still elusive. Here, using a constructive approach, it is demonstrated that the co‐existence of various macromolecules themselves has the ability to tune protein localization for spatiotemporal regulation and a biochemical reaction system in a cell‐size space. Both experimental and theoretical analyses reveal that enhancement of interfacial effects by a large surface‐area‐to‐volume ratio facilitates membrane localization of molecules in the cell‐size space, and the interfacial effects are alleviated by competitive binding to lipid membranes among multiple proteins even if their membrane affinities are weak. These results indicate that competition for membrane binding among various macromolecules in the cell‐size space plays a role in regulating the spatiotemporal molecular organization and biochemical reaction networks. These findings shed light on the importance of surrounding molecules for biochemical reactions using purified elements in small spaces. [ABSTRACT FROM AUTHOR]

Transport of macromolecules from the nucleus to the cytoplasm is essential for nearly all cellular and developmental events, and when mis‐regulated, is associated with diseases, tumor formation/growth, and cancer progression. Nuclear Envelope (NE)‐budding is a newly appreciated nuclear export pathway for large macromolecular machineries, including those assembled to allow co‐regulation of functionally related components, that bypasses canonical nuclear export through nuclear pores. In this pathway, large macromolecular complexes are enveloped by the inner nuclear membrane, transverse the perinuclear space, and then exit through the outer nuclear membrane to release its contents into the cytoplasm. NE‐budding is a conserved process and shares many features with nuclear egress mechanisms used by herpesviruses. Despite its biological importance and clinical relevance, little is yet known about the regulatory and structural machineries that allow NE‐budding to occur in any system. Here we summarize what is currently known or proposed for this intriguing nuclear export process. [ABSTRACT FROM AUTHOR]

Activated carbons obtained via the thermochemical treatment of lemon balm and mint herbs were applied for ionic polymers adsorption, which directly affects the stability of these types of aqueous suspensions. The examined carbonaceous materials were characterized by well-developed specific surface area (approximately 1000 m2/g) and mesoporous structure. The adsorbed amounts of anionic poly(acrylic acid) and cationic polyethyleneimine from one-component solutions reached significant levels, but the efficiency of adsorption of these compounds from binary solutions slightly decreased. Moreover, the ionic polymers showed stabilizing properties towards the activated carbons suspensions. For both adsorbents, the most stable suspensions were systems containing both types of polymeric macromolecules with different ionic characters. This was due to the occurrence of electrosteric and depletion stabilization mechanisms. Furthermore, the zeta potential and size of particle aggregates were also influenced by the presence of polymers in the aqueous suspensions of activated carbons. [ABSTRACT FROM AUTHOR]

It was found that in the region of the percolation threshold, depending on the dominance of one or another conduction mechanism, the temperature dependence of the specific volume resistivity ρ(T) of the polymer composite based on a matrix of ethylene vinyl acetate is significantly transformed. With an increase in the CB content, there is a decrease by several orders of magnitude in the maximum value of the relative resistivity ρ(T)max/ρ20 in its temperature dependence. Peroxide crosslinking of matrix macromolecules leads to a change in the nature of the temperature dependence of resistivity. [ABSTRACT FROM AUTHOR]

The large molecular weight of the macromolecules sets them apart from all other components. This may range from 10 000 to over a million. While the molecular weight of other plant metabolites is seldom beyond 1000. Chemically, macromolecules are made up of long chains and little "building pieces," which are joined covalently in a variety of ways. Biological macromolecules are large, naturally occurring cellular building blocks that play a range of crucial roles in the development and existence of living organisms. Biomacromolecules are essential in the biomedical field and other related professions. They feature a variety of beneficial properties, including excellent biodegradability, suitable mechanical strength, enhanced bioavailability, etc. They also have significant biocompatibility. They display a variety of biological characteristics, such as antimalignant, antidiabetic, antibacterial, antioxidant, and immunomodulatory. The use of essential carbohydrates including alginate, chitosan, pectin, starches, carrageenan, fucoidan, etc. is common in commercial applications. Natural substance‐based pharmacotherapy is now considered to be a highly promising future alternative to conventional medicine. Along with proteins and polynucleotides, polysaccharide is a vital biomacromolecule that has a crucial function in the growth and expansion of living things. A crucial element of higher plants, cell membranes of animal, and cell walls of microbes is polysaccharide. It is intimately tied to physiological processes as well. The importance of polysaccharides as a significant class of bioactive natural compounds has received more attention recently. Numerous studies have shown that natural polysaccharides contain bioactivities, which have led to the use of polysaccharides in the treatment of illness. The many parts of the research findings on the bioactivities of polysaccharides in gastro‐protection are included in this paper. [ABSTRACT FROM AUTHOR]

The concept of macromolecules, which is applied to synthetic and natural polymers, allows for various contemporary polymeric materials and inventive uses. A dynamic structure of macromolecules called the extracellular matrix (ECM) maintains tissues and organs functioning. The cell therapy procedure known as wound healing involves depositing ECM components such as collagen, fibronectin, and laminin. The clinical assessment and management of wounds remain challenging despite the introduction of numerous therapeutic regimens because of their laboriously prolonged treatment requirements and complex wound‐healing mechanisms using macromolecules of a specific type, such as proteins, carbohydrates, lipids, and nucleic acids. Additionally, proteins affect the wound site's mechanical characteristics, such as tensile strength, elasticity, and permeability, which impact the effectiveness and success of wound healing. The main goal of this article is to give a current overview of how therapeutic alternatives have evolved using cutting‐edge innovative techniques for the healing and treatment of wounds. In this article, we have covered different types of macromolecules, how diet affects the wound, what causes wounds, and how macromolecules can help, and how to treat wounds. [ABSTRACT FROM AUTHOR]

Poly(N-vinyl succinimides) synthesized by classical radical polymerization are studied by the methods of molecular hydrodynamics in dilute solutions in dimethylformamide within a 40-fold MM range. The molecular characteristics and scaling ratios of poly(N-vinyl succinimide) molecules are determined, and their equilibrium rigidity is estimated. [ABSTRACT FROM AUTHOR]